A new strategy in selective harmonic elimination for a photovoltaic multilevel inverter

Abstract

Selective harmonic elimination technology (SHE) has been widely used in many medium and high power converters. Because of low switching frequency privilege in this method, low power loss is expected in the converters. Although it is still a crucial work to find optimum switching angle from a group of nonlinear transcendental equations, especially in multilevel inverters with multiple switching in each level. In this article a new strategy based on selective harmonic elimination concept (SHE-PWM) in photovoltaic multilevel inverter with multiple switching is proposed. In the proposed strategy, the solving process is divided into two steps to ease the complexity of the problem and increase the degree of control in each step. It also offers an exclusive searching scheme which makes convergence easily achievable. Simulation's result also proves validity of the proposed strategy for a wide range of modulation indices.